The Japan Aerospace Exploration Agency (JAXA) has just completed the first year of its analytical campaign on samples returned from asteroid Ryugu. These cutting-edge studies have been undertaken by two Phase-2 curation teams (the Kochi Institute for Core Sample Research, Japan Agency for Marine-Earth Science and Technology, JAMSTEC and Okayama University) and six sub-teams of the Initial Analysis Team.
We are pleased to announce that a journal article summarizing the results of the Phase-2 Kochi Team has been published in “Nature Astronomy” on August 16, 2022 (JST).
According to JAXA, sample from asteroid Ryugu returned to Earth by the asteroid explorer, Hayabusa2, on December 6, 2020, initially underwent a cataloguing description (Phase-1 curation) at the facility established at JAXA’s Institute of Space and Astronautical Science. Part of the returned sample was distributed to the Hayabusa2 Initial Analysis Team, consisting of six sub-teams, and two Phase-2 curation institutes at Okayama University and JAMSTEC Kochi Institute for Core Sample Research.
In its report, the initial analysis is designed to reveal the multifaceted features of the sample through a plan of high-precision analysis, with specialized sub-teams assigned to tackle the science objectives of the Hayabusa2 mission. Meanwhile, the Phase-2 curation institutes have specific specialties that are utilized to catalogue the sample based on a comprehensive analysis flow, and clarify the potential impact of the sample through measurement and analysis appropriate to the characteristics of the returned particles.
Reports from the six teams involved in the initial analysis, as well as those from Okayama University and JAMSTEC Kochi Institute for Core Sample Research, will be announced separately as the results are published in scientific journals. After the initial results have been released, a new overall summary of the Hayabusa2 science is planned.
The agency said, “The Phase-2 curation Kochi Team has been working with JAXA curation since 2015 to improve sample storage and transportation, analytical techniques of extraterrestrial materials, and curatorial activities”.
In mid-June of 2021, eight Ryugu particles (four from chamber A, four from chamber C; particles have a diameter of 1–4 mm), approximately 50 mg in total, were allocated to the Kochi Team. The X-ray computed tomography (CT) imaging was performed at the SPring-8 synchrotron radiation facility to assess the three-dimensional shapes and internal structures of individual particles and to determine the regions-of-interests for subsequent analyses.
The particles were then transported to domestic and international research institutes without exposure to the Earth’s atmosphere. With the cooperation of the British Embassy in Japan, the Ministry of Education, Culture, Sports, Science and Technology of Japan, and the Ministry for Foreign Affairs of Japan, the samples were safely and quickly transported to the Open University, UK and the Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles (UCLA), USA.